add 3090

Author: fishercoder1534

Diff for: paginated_contents/algorithms/4th_thousand/README.md

@@ -30,6 +30,7 @@
 | 3120 | [Count the Number of Special Characters I](https://leetcode.com/problems/count-the-number-of-special-characters-i/)                                                 | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/fourththousand/_3120.java) |                                                                               | Easy       |
 | 3110 | [Score of a String](https://leetcode.com/problems/score-of-a-string/)                                                 | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/fourththousand/_3110.java) |                                                                               | Easy       |
 | 3095 | [Shortest Subarray With OR at Least K I](https://leetcode.com/problems/shortest-subarray-with-or-at-least-k-i/)                                                                                                   | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/fourththousand/_3095.java) |                                                                               | Easy       |
+| 3090 | [Maximum Length Substring With Two Occurrences](https://leetcode.com/problems/maximum-length-substring-with-two-occurrences/)                                                                                                   | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/fourththousand/_3090.java) |                                                                               | Easy       |
 | 3074 | [Apple Redistribution into Boxes](https://leetcode.com/problems/apple-redistribution-into-boxes/)                                                                                                   | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/fourththousand/_3074.java) |                                                                               | Easy       |
 | 3062 | [Winner of the Linked List Game](https://leetcode.com/problems/winner-of-the-linked-list-game/)                                                                                                   | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/fourththousand/_3062.java) |                                                                               | Easy       |
 | 3046 | [Split the Array](https://leetcode.com/problems/split-the-array/)                                                                                                   | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/fourththousand/_3046.java) |                                                                               | Easy       |

Diff for: src/main/java/com/fishercoder/solutions/fourththousand/_3090.java

@@ -0,0 +1,31 @@
+package com.fishercoder.solutions.fourththousand;
+
+public class _3090 {
+    public static class Solution1 {
+        public int maximumLengthSubstring(String s) {
+            int max = 0;
+            int[] count = new int[26];
+            for (int left = 0, right = 0; right < s.length() && left < s.length(); ) {
+                if (qualified(count, s.charAt(right))) {
+                    max = Math.max(max, right - left + 1);
+                    right++;
+                } else {
+                    count[s.charAt(left) - 'a']--;
+                    left++;
+                }
+            }
+            return max;
+        }
+
+        private boolean qualified(int[] count, char charAt) {
+            count[charAt - 'a']++;
+            for (int c : count) {
+                if (c > 2) {
+                    count[charAt - 'a']--;
+                    return false;
+                }
+            }
+            return true;
+        }
+    }
+}

Diff for: src/test/java/com/fishercoder/fourththousand/_3090Test.java

@@ -0,0 +1,22 @@
+package com.fishercoder.fourththousand;
+
+import com.fishercoder.solutions.fourththousand._3090;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class _3090Test {
+    private static _3090.Solution1 solution1;
+
+    @BeforeEach
+    public void setup() {
+        solution1 = new _3090.Solution1();
+    }
+
+    @Test
+    public void test1() {
+        assertEquals(4, solution1.maximumLengthSubstring("bcbbbcba"));
+    }
+
+}